Common equipment failures and how to prevent them.

Bent

I got nothin'
The house is quiet, the kids and the wife are gone out of the house for a few hours, and you have time to just sit and watch the tank. That stupid fish tank that you have spent countless hours, blood and sweat getting just perfect. So you grab your coffee, or beer, or glass of wine, pull up your favorite chair and...

*splash*

Your feet are wet and you are trudging through 1" deep water on your hardwood floors. Your mind races, your looking for the problem, now your few hours of rest and relaxation has turned into a blood pressure skyrocketing, stroke inducing, "ow my left arm hurts", sphincter tightening, full on DEFCON3, white knuckled, panic.

You've seen the pics, you've read the stories and most of us think, "this'll never happen to me." The sad reality is, that your wrong. Equipment failures will happen to you! There is no two ways about it, no matter how much you plan, no matter how smart you are, something, somewhere is going to go horribly, horribly wrong.

That's the bad news. The good news is, however, that even when an equipment failure happens, this scenario does not need to happen to you. This post is going to outline just how to prevent a catastrophic equipment failure from sending you or your loved ones to the cardiac cath lab at your local hospital and give you piece of mind that an equipment failure when it does happen, will not be the end of you or cause hundreds of thousands of dollars of damage to your home.

First of all, we need to identify the most common points of failure, what a failure will do, and go over how to prevent collateral damage by using a minimum of three redundancies on each system.

So in no particular order, we will begin:

I: The ATO.

Generally, the auto top off has a single point of catastrophic failure, the float switch or optical switch that is being used to maintain the water level in the sump. Should this switch fail in the on position, then the amount of water in the ATO reservoir will be dumped into the sump. If the ATO reservoir is your RO/DI storage container and has an endless supply of water, then you are going to end up flooded. How to prevent this:

A: do not use the RO/DI storage container as the ATO reservoir.
This seems elementary given that this is the main culprit for the flooding in the first place, but the "set and forget" aspect of it is pretty tantalizing. Don't give in to it. Use a separate container to place your ATO pump in and make sure that the sump can handle the entire volume of the ATO reservoir. If that means you have to fill the ATO container once every couple of weeks, then so be it. It can still be plumbed up so that you don't have to carry buckets however. Put a pump inside your RO/DI container for instance and plumb it to your container. Put that pump on a switch so that all you have to do to fill the container is to flip the switch. Or you can gravity feed it with a ball valve from the RO/DI container. It does not really matter how you do it, just that you are the one physically filling the ATO.

B: Place the ATO pump on a timer.
Instead of letting the ATO pump trickle in all day long, place it on a timer so that the pump only comes on once or twice a day. Preferably when you are more likely to be home. This will also let you work in the sump without the ATO pump kicking on and off.

C: Use a double float switch.
Instead of a single float, a double float setup that has a second "emergency" float reversed. Place this at your highest tolerable water level in the sump. So this way if the first float fails, the second float will turn the pump off.

D: install a third panic switch that can operate alarm systems.
There are tons of products out there that can alert you multiple ways, from screeching a loud annoying alarm, to texting you that it has been tripped. Hook one or all of these up to a "panic" float switch.

E: install water alarms around the sump.
Water alarms are all over Amazon. Some of them will just buzz loudly when water is detected, some are pretty sophisticated and can actually email or text you when water is detected.

F: install an overflow drain.
This is probably the best way to prevent flood, but requires pretty significant modifications to your home. A floor drain or a drain that's lower than your highest acceptable water level can be a life safer. Simply drill the sump and route a pipe downhill to the drain. This method the sump will never overflow.

G: use two ATO pumps.
While a pump sticking on can cause problems, a raising SG from a burned out pump can also wreak havoc on your tank. So I always suggest plumbing at least two ATO pumps up to the same switch, so if one of them breaks, you will still be operational.

II: the RO/DI storage container.

Not many people think of the RO/DI storage container flooding, but it can happen. You want the container full, but if something screws up, you may find it overflowing.

A: put a float valve on the inlet.
A float valve on the inlet of the unit inside the RO/DI container will help prevent a flood by mechanically shutting off the water flow should the water level rise to that point.

B: a normal closed solenoid.
Placing a normally closed solenoid on the water inlet to the entire unit, and placing it on a timer will prevent the unit from running all day long. A normally closed solenoid will remain closed until it is powered. Once powered, the solenoid will open and allow the water to flow to the unit. Most RO/DI units will shut the booster pump off automatically after a certain amount of time if it does not receive any water. So putting the solenoid on a timer will allow you to dictate when the unit comes on and when it turns off.

C: a float switch inside the container.
Placing a float switch in the container and plugging the booster pump up to it will shut off the booster pump should the water level rise to the point it is triggered.

D: a water alarm

E: a drain.
Once again, placing a drain at the highest acceptable water level in the container and routing it to a drain is the best way to prevent a flood, but not always feasible. Mine is routed to the mop sink.

III: the skimmer.

Seemingly innocuous, the ole protein skimmer, if it is routed to a container outside the sump, can and will flood. If the Venturi input of the pump gets clogged, then water will be pumped up into the collection cup and into the container until it floods:

A: don't route the output outside the sump.
Seems elementary again, but for those of us not wanting to clean the cup every freaking day, this just isn't an option. Plus overflowing skimmer gunk floating in the sump is just gross. However, if you are dedicated and clean the cup out regularly, keeping the output line inside the sump ensures that it will never cause a flood.

B: place a float switch in your container that will shut the skimmer pump off should the water level rise to that point. Avast marine makes a killer skimmate locker that uses a pressure switch that shuts the pump off when the locker gets full. I use it after 3 rounds of DIY trying to make one.
http://avastmarine.com/collections/avast-built/products/djsl-xl
http://avastmarine.com/collections/avast-built/products/djsl

C: a float switch in the sump.
This will shut the skimmer off if it is tripped. This will prevent overflows by shutting the skimmer pump off once the water level rises to your predetermined point.

D: a water alarm.

IV: the return pump.

This is probably the most common cause of a flood. It happens during a power failure from water being back siphoned through the return plumbing back into the sump. Siphoning is physics folks. You can't stop it, but you can control the amount that is siphoned a couple of ways.

A: place the return outlets as close to the water surface as possible.
The siphon will break if enough air is introduced. So the best way to prevent it is to route the return nozzles as close to, or even above the waters surface.

B: make sure the sump can handle the volume of water being siphoned in the event of a power failure.
If you have a 125 gallon tank, with return nozzles at the bottom, and a 20g sump, this isn't going to end well....

C: drill a siphon break hole just above the water surface in the return plumbing.
Of course this isn't so easy to do unless the return line is looped over the back of the display tank, plus it's not 100% fool proof. Salt creep, critters, gunk, etc. can all plug the hole and you'll still end up with water on the floor. Return to option B.

D: check valves.
While some people will turn their noses up at this, check valves have their uses. There are more than one type and the type that allows you to clean it the most and easiest is the type you should go with. The proper use for a check valve is with long and extensive return plumbing to prevent air and water from being shot gunned out of the return outlets when the power comes back on. While using one as 100% of your defense against back siphoning is ill advised, they can be useful as secondary or tertiary insurance plans used in conjunction with other fail safes and as mentioned can help with the shot gun spray of water and air when the power is restored.

V: the overflow

Clogged, blocked and noisy single durso overflows are the biggest reasons that both the herbie and bean methods of overflow plumbing exist. I can't tell you how many horror stories I've read, and experienced with a single durso overflow clogging up for whatever reason, and spilling the contents of the sump all over the living room floor. While some people will say that they have used a single durso outlet for years without any problem, I will come back and say that failing to plan, is planning to fail.

https://www.youtube.com/watch?v=q1tAnhIGpgA

A: the herbie method:
http://reefcentral.com/forums/showthread.php?t=344892

B: the bean animal method:
http://www.reefcentral.com/forums/showthread.php?threadid=1310585

In conclusion, not adding secondary and tertiary fail safes when it comes to something that holds hundreds of gallons of corrosive saltwater is playing with fire. Being able to leave your system for a week or the weekend and not worry every waking second is worth any amount of time and effort setting up these fail safes. Don't say, "it won't happen to me" because it will, sooner or later, it will. It's just the law of averages. If you spend the time and energy to do this hobby in a way that lets you worry the least, you will get much more enjoyment from it. So now instead of saying "it'll never happen to me", you can say "it'll happen to me, but I'm ready".

Happy reefing.

Ben
 
Last edited:
Great write-up. Everyone should plan for theses or expect to pay more to have the floors fixed.

On the other hand I have some new flooring in the house which is nice.
 
Use a controller with automatic leak detection. I have an Apex with the leak detection modules and if even a hint of water is sensed (they have been known to go off on the concrete floor just from the moisture the concrete will pick up) and anything that move water, including all dosing pumps, shuts down until I determine the problem and tell the system the problem is fixed.

Yes, it still needs reasonable pack ups in place in the event that it fails, but it two years (knocking on wood) it hasn't faile to find a leak.

If you are using peristaltic pumps you never know when one might split. Caution says change every six months
 
Use a controller with automatic leak detection. I have an Apex with the leak detection modules and if even a hint of water is sensed (they have been known to go off on the concrete floor just from the moisture the concrete will pick up) and anything that move water, including all dosing pumps, shuts down until I determine the problem and tell the system the problem is fixed.

Yes, it still needs reasonable pack ups in place in the event that it fails, but it two years (knocking on wood) it hasn't faile to find a leak.

If you are using peristaltic pumps you never know when one might split. Caution says change every six months

oh yeah absolutely reef controllers are cool and really nice and definitely a worthwhile investment, I was just throwing out some more options for poor people like myself lol.

Edit:
That's a great point about the peristaltic pumps too, I'll have to remember that.
 
As others have said, thank you for a great write up sir. And while maybe not AS costly as a flood, don't forget heaters! A simple controller and backup heater could very well be a small investment that saves thousands in event of failure.
 
As others have said, thank you for a great write up sir. And while maybe not AS costly as a flood, don't forget heaters! A simple controller and backup heater could very well be a small investment that saves thousands in event of failure.

That's a great point! I forgot all about that.

Yes it's very important to use a ranco or something similar hooked up to multiple heaters in case one of them fails.
 
Back
Top